// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/base/models/list_model.h"

#include <stddef.h>

#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/scoped_ptr.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace ui {

class FooItem {
public:
    explicit FooItem(int id)
        : id_(id)
    {
    }

    int id() const { return id_; }

private:
    int id_;
    DISALLOW_COPY_AND_ASSIGN(FooItem);
};

class ListModelTest : public testing::Test,
                      public ListModelObserver {
public:
    ListModelTest()
        : added_count_(0)
        , removed_count_(0)
        , moved_count_(0)
        , changed_count_(0)
    {
    }

    void ExpectCountsEqual(size_t added_count,
        size_t removed_count,
        size_t moved_count,
        size_t changed_count)
    {
        EXPECT_EQ(added_count, added_count_);
        EXPECT_EQ(removed_count, removed_count_);
        EXPECT_EQ(moved_count, moved_count_);
        EXPECT_EQ(changed_count, changed_count_);
    }

    void ClearCounts()
    {
        added_count_ = removed_count_ = moved_count_ = changed_count_ = 0;
    }

    // ListModelObserver implementation:
    void ListItemsAdded(size_t start, size_t count) override
    {
        added_count_ += count;
    }
    void ListItemsRemoved(size_t start, size_t count) override
    {
        removed_count_ += count;
    }
    void ListItemMoved(size_t index, size_t target_index) override
    {
        ++moved_count_;
    }
    void ListItemsChanged(size_t start, size_t count) override
    {
        changed_count_ += count;
    }

private:
    size_t added_count_;
    size_t removed_count_;
    size_t moved_count_;
    size_t changed_count_;

    DISALLOW_COPY_AND_ASSIGN(ListModelTest);
};

TEST_F(ListModelTest, Add)
{
    ListModel<FooItem> model;
    model.AddObserver(this);

    // Append FooItem(0)
    model.Add(new FooItem(0));
    ExpectCountsEqual(1, 0, 0, 0);

    // Append FooItem(1)
    model.Add(new FooItem(1));
    ExpectCountsEqual(2, 0, 0, 0);

    // Insert FooItem(2) at position 0
    model.AddAt(0, new FooItem(2));
    ExpectCountsEqual(3, 0, 0, 0);

    // Total 3 items in model.
    EXPECT_EQ(3U, model.item_count());

    // First one should be FooItem(2), followed by FooItem(0) and FooItem(1)
    EXPECT_EQ(2, model.GetItemAt(0)->id());
    EXPECT_EQ(0, model.GetItemAt(1)->id());
    EXPECT_EQ(1, model.GetItemAt(2)->id());
}

TEST_F(ListModelTest, Remove)
{
    ListModel<FooItem> model;
    model.AddObserver(this);

    model.Add(new FooItem(0));
    model.Add(new FooItem(1));
    model.Add(new FooItem(2));

    ClearCounts();

    // Remove item at index 1 from model and release memory.
    model.DeleteAt(1);
    ExpectCountsEqual(0, 1, 0, 0);

    EXPECT_EQ(2U, model.item_count());
    EXPECT_EQ(0, model.GetItemAt(0)->id());
    EXPECT_EQ(2, model.GetItemAt(1)->id());

    // Remove all items from model and delete them.
    model.DeleteAll();
    ExpectCountsEqual(0, 3, 0, 0);
}

TEST_F(ListModelTest, RemoveAll)
{
    ListModel<FooItem> model;
    model.AddObserver(this);

    scoped_ptr<FooItem> foo0(new FooItem(0));
    scoped_ptr<FooItem> foo1(new FooItem(1));
    scoped_ptr<FooItem> foo2(new FooItem(2));

    model.Add(foo0.get());
    model.Add(foo1.get());
    model.Add(foo2.get());

    ClearCounts();

    // Remove all items and scoped_ptr above would release memory.
    model.RemoveAll();
    ExpectCountsEqual(0, 3, 0, 0);
}

TEST_F(ListModelTest, Move)
{
    ListModel<FooItem> model;
    model.AddObserver(this);

    model.Add(new FooItem(0));
    model.Add(new FooItem(1));
    model.Add(new FooItem(2));

    ClearCounts();

    // Moves item at index 0 to index 2.
    model.Move(0, 2);
    ExpectCountsEqual(0, 0, 1, 0);
    EXPECT_EQ(1, model.GetItemAt(0)->id());
    EXPECT_EQ(2, model.GetItemAt(1)->id());
    EXPECT_EQ(0, model.GetItemAt(2)->id());
}

TEST_F(ListModelTest, FakeUpdate)
{
    ListModel<FooItem> model;
    model.AddObserver(this);

    model.Add(new FooItem(0));
    model.Add(new FooItem(1));
    model.Add(new FooItem(2));

    ClearCounts();

    model.NotifyItemsChanged(0, 1);
    ExpectCountsEqual(0, 0, 0, 1);

    model.NotifyItemsChanged(1, 2);
    ExpectCountsEqual(0, 0, 0, 3);
}

} // namespace ui
